You didn't say explictely what you want to get from the network configuration.
Is it something like this you are looking for ?
Get-VM|where {$_.Guest.ExtensionData.GuestFamily-match"windows"} |
Get-VMGuestNetworkInterface|Select@{N="VM";E={$_.VM.Name}},Name,Ip,SubnetMask,DefaultGateway,
@{N="DNS";E={[string]::Join(',',$_.Dns)}},
@{N="Wins";E={[string]::Join(',',$_.Wins)}}
As you might notice there will be some internal NICs in the output (loopback adapters....).
These can be excluded with a Where-clause if needed.